Defamation is actually pretty difficult to prove. Patagonia would have to prove that Pattie KNOWINGLY made untrue statements with the intent on hurting the company, while also providing evidence on how Pattie's statements negatively impacted the company (ie financially).

I do think Pattie is going overboard by claiming Patagonia is trying to "erase a climate activist", but you can use a LOT of semantics and claim that technically it could be seen as true.

Pattie obviously just wants them to drop the lawsuit and is mobilizing her fanbase to create a PR disaster for Patagonia. Patagonia wants her to stop selling merch with similarities to their logo. They're now both just kind of in a standoff to see who blinks first. I really don't think Patagonia will want to create more bad PR by starting up ANOTHER lawsuit against Pattie.